Over 900 domestic cats were tracked with GPS collars from six different countries. The large majority of the cats were from Australia, New Zealand, the United Kingdom and the United States. Their spatial-temporal data was recorded for a range of 1 to 549 days and was retrieved from movebank.org (Roetman and Tindle 2020)(Kikillus and Woods 2020)(McDonald and Cole 2020)(R Kays et al. 2020). The metadata consisted of age, sex, neutered/spayed status, and the owner reported number of prey killed. The focus of the study was to understand the spatial context of their movement to assess the ecological impacts of these predators (R. Kays et al. 2020).
A defining characteristic of animal movement data are when animals are tracked. Often groups of animals are tracked in different time periods. Understanding this information is the first step before movement analysis can be performed.
The first plot shows the length of time cats were tracked per region. We can immediately draw some useful information. Australia has the largest number of cats that were tracked. The United States had several cats that were tracked for longer than average periods. The cats from New Zealand were tracked in roughly the same time frame as Australia.
The densities below the plot show a clearer relationship of the time overlap between countries. They also provide more immediate information about the number of cats tracked in a time period versus the line plot which consists of tightly packed lines.
The interactivity allows us to gain more information about individual cats including name, country, date deployed and days tracked. By zooming in and using the tooltip we can find out that the longest cat tracked is from the United States, is named Oscar.L, and was tracked for 549 days starting in November 2014.